Rotor blades for wind turbine are usually built as fibre-reinforced hollow composite structures. Hence, they are usually fabricated by impregnating respective aligned and orientated fibres or fibre clutches with a casting or resin material respectively. Thereby, removing of the cast rotor blade is oftentimes problematic since particularly in the region of the ring-like shaped root of the blade ovalisation may occur due to the self-weight of the rotor blade. Respective ovally shaped or deformed rotor blades are difficult to machine and particularly difficult to mount on a respective rotor hub of a wind turbine.